Forensic Science

T. Trimpe 2006 http://sciencespot.net

CRIME SCENE: Any physical location in which a crime has occurred or is suspected of having occurred.

Source: http://www3.sc.maricopa.edu/ajs/crime_scene_technician.htm

PRIMARY CRIME SCENE: The original location of a crime or accident.

SECONDARY CRIME SCENE: An alternate location where additional evidence may be found.

ALIBI: Statement of where a suspect was at the time of a crime.

ACCOMPLICE: Person associated with someone suspected of committing a crime.

SUSPECT: Person thought to be capable of committing a crime.

Crime Scene Vocabulary

Source: http://www3.sc.maricopa.edu/ajs/crime_scene_technician.htm

What will evidence collected at a scene do for the investigation?

• May prove that a crime has been committed• Establish key elements of a crime• Link a suspect with a crime scene or a victim• Establish the identity of a victim or suspect• Corroborate verbal witness testimony • Exonerate the innocent. • Give detectives leads to work with in the case

POLICE OFFICERS are typically the first to arrive at a crime scene. They are responsible for securing the scene so no evidence is destroyed and detaining persons of interest in the crime.

The CSI UNIT documents the crime scene in detail and collects any physical evidence.

The DISTRICT ATTORNEY is often present to help determine if any search warrants are required to proceed and obtains those warrants from a judge.

The MEDICAL EXAMINER (if a homicide) may or may not be present to determine a preliminary cause of death.

SPECIALISTS (forensic entomologists, anthropologists, or psychologists) may be called in if the evidence requires expert analysis.

DETECTIVES interview witnesses and consult with the CSI unit. They investigate the crime by following leads provided by witnesses and physical evidence.

Source: http://science.howstuffworks.com/csi.htm

Crime Scene Personnel

Step 1: InterviewThe first step in investigating a crime scene is to interview the first officer at the scene or the

victim to determine what allegedly happened, what crime took place, and how was the crime committed. This information may not be factual information but it will give the investigators a place to start.

Step 2: ExamineThe second step in the investigation of a crime scene, which will help identify possible

evidence, identify the point of entry and point of exit, and outline the general layout of the crime scene.

Step 3: DocumentThe third step in the protocol involves creating a pictorial record of the scene as well as a

rough sketch to demonstrate the layout of the crime scene and to identify the exact position of the deceased victim or other evidence within the crime scene.

Step 4: ProcessThis is the last step in the protocol. The crime scene technician will process the crime scene

for evidence, both physical and testimonial evidence. It is the crime scene technicians responsibility to identify, evaluate and collect physical evidence from the crime scene for further analysis by a crime laboratory.

Crime Scene Protocol

Adapted from http://www.feinc.net/cs-proc.htm